/Engine/Source/Runtime/ApplicationCore/Public/GenericPlatform/Accessibility/GenericAccessibleInterfaces.h
Registers an accessible user with the accessible registry. It is up to the caller to ensure that the passed in user has the correct user index. The passed in user will not be registered if another user with the same user index has already been registered. This function callsFGenericAccessibleUser::OnRegisteredif the passed in user is successfully registered. Once an accessible user has been successfully registered, it can be retrieved and interacted with by the rest of the application.
True if the passed in user was successfully registered. Else, returns false.
bool RegisterUser ( const [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [FGenericAccessibleUser](API\Runtime\ApplicationCore\GenericPlatform\Accessibility\FGenericAccessibleUser) > & User )